Problem: Khan.scratchpad.disable(); Vanessa sells magazine subscriptions and earns $$9$ for every new subscriber she signs up. Vanessa also earns a $$30$ weekly bonus regardless of how many magazine subscriptions she sells. If Vanessa wants to earn at least $$86$ this week, what is the minimum number of subscriptions she needs to sell?
Explanation: To solve this, let's set up an expression to show how much money Vanessa will make. Amount earned this week $=$ $ $ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus Since Vanessa wants to make at least $$86$ this week, we can turn this into an inequality. Amount earned this week $\geq $86$ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus $\geq $86$ We are solving for the number of subscriptions sold, so let subscriptions sold be represented by the variable $x$ We can now plug in: $x \cdot $9 + $30 \geq $86$ $ x \cdot $9 \geq $86 - $30 $ $ x \cdot $9 \geq $56 $ $x \geq \dfrac{56}{9} \approx 6.22$ Since Vanessa cannot sell parts of subscriptions, we round $6.22$ up to $7$ Vanessa must sell at least 7 subscriptions this week.